It is known from our published UK patent application No. GB2374121A to provide a plurality of circumferentially arranged movable tabs at the downstream end of a turbofan gas turbine engine exhaust nozzle. The tabs are moved between a non-deployed and a deployed position to reduce exhaust noise while in the deployed position.
It is also known from GB2374121A to provide a plurality of circumferentially arranged fixed tabs and a plurality of circumferentially arranged movable tabs at the downstream end of the turbofan gas turbine engine exhaust nozzle. The fixed tabs and movable tabs are arranged circumferentially alternately. The movable tabs are moved between a non-deployed and a deployed position. The movable tabs reduce exhaust noise while in the deployed position. The movable tabs are circumferentially aligned with the fixed tabs in the non-deployed position to reduce aerodynamic drag.
It is also known from GB2374121A to provide a plurality of circumferentially arranged fixed tabs and a plurality of circumferentially arranged movable tabs at the downstream end of the turbofan gas turbine engine exhaust nozzle. The fixed tabs and movable tabs are arranged circumferentially alternately. The movable tabs are moved between a non-deployed and a deployed position. The fixed tabs reduce exhaust noise when the movable tabs are in the deployed position and the movable tabs increase the area of the nozzle to compensate for the reduction in the area due to the fixed tabs. The movable tabs are circumferentially aligned with the fixed tabs in the non-deployed position to reduce aerodynamic drag.